SQL Server

Decompress Gzip Data from BinData Directly to a File

See more Gzip Examples

This example demonstrates how to use the UncompressBdToFile method to decompress Gzip data stored in a BinData object and write the uncompressed output directly to a file.

The compressed .gz data is first loaded into memory using a BinData object. The UncompressBdToFile method then decompresses the data and writes the result directly to the specified file, without modifying the contents of the BinData object.

This approach is useful when you want to extract compressed data to disk without performing an in-place transformation or managing intermediate buffers.

SQL Server

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    -- This example demonstrates how to decompress Gzip data stored in a BinData object
    -- and write the uncompressed output directly to a file.

    DECLARE @gzip int
    EXEC @hr = sp_OACreate 'Chilkat.Gzip', @gzip OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @bd int
    EXEC @hr = sp_OACreate 'Chilkat.BinData', @bd OUT

    -- Load a .gz file into BinData:
    EXEC sp_OAMethod @bd, 'LoadFile', @success OUT, 'example.txt.gz'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @bd, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @gzip
        EXEC @hr = sp_OADestroy @bd
        RETURN
      END


    PRINT 'Loaded Gzip data into memory.'

    -- Uncompress the Gzip data and write directly to a file:
    EXEC sp_OAMethod @gzip, 'UncompressBdToFile', @success OUT, @bd, 'example.txt'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @gzip, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @gzip
        EXEC @hr = sp_OADestroy @bd
        RETURN
      END


    PRINT 'File successfully uncompressed to example.txt'

    EXEC @hr = sp_OADestroy @gzip
    EXEC @hr = sp_OADestroy @bd


END
GO